Description based on 1975/1976.; Subtitle varies.; Also called: BSC catalog.; Issued in electronic format beginning in 1998.; No catalogue issued for 1989/1990.; Enumeration varies: 1979/1981 is a sequential catalogue to the 1977/1978 issue, 1983/1985 is a sequential catalogue to the 1982/1983 issue, 2004/2006 is a sequential catalog to the 2003/2004 issue.; Supplement issued separately for 1987/1988 catalogue.